Nonlinear magneto-acoustics of tetragonal antiferromagnets

The results of theoretical study of the influence of mechanical stress, ele ctric and magnetic fields on the conditions for magneto-elastic solitons ex istence and their dynamic properties in the symmetric phase of a tetragonal antiferromagnet are presented. The conditions for the occurrence of nonlin ear magneto-elastic resonance of long and short waves (which is analogous t o the Zakharov-Benney triad resonance) in this system are derived. The poss ibility of experimental detection of this new phenomenon is discussed.